Internal combustion engines



Feb. 9, .1960 c. E. SUMMERS 2,924,210

INTERNAL COMBUSTION ENGINES Original Filed Sept. 27, 1956 4 Sheets-Sheet 2 HOE HOA

INVENTOR.

CALEB E. SUMMERS Feb. 9, 1960 c. E. SUMMERS 2,924,210

INTERNAL COMBUSTION ENGINES Original Filed Sept. 27, 1956 4 Sheets-Sheet a FIG.6.

FIG .5. 2/4

INVENTOR.

Feb. 9, 1960 c. E. SUMMERS INTERNAL COMBUSTION ENGINES Original Filed Sept. 27, 1956 4 Sheets-Sheet 4 INVENTOR. 547:; ld'azrrrmers. BY

24:. razu z/ e'.

INTERNAL COMBUSTION ENGINES Caleb E. Summers, Orchard Lake, Mich.

Continuation of abandoned application Serial No. 612,450, September 27, 1956. This application August 8, 1958, Serial No. 754,092

34 Claims. (Cl. 123-191) The present invention relates to internal combustion engines of the Otto cycle type and specifically to methods and/ or means for controlling the combustion of fuel in such engines.

The present application is a continuation of my previously filed copending application Serial No. 612,450 filed September 27, 1956, now abandoned, as to all subject matter common to the two. Said application Serial No. 612,450 was a continuation-in-part of each of two applications filed theretofore but copending therewith and identified as applications Serial Nos. 152,940, filed March 30, 1950, now abandoned, and Serial No. 317,035, filed October 27, 1952, now abandoned.

Among the objects of the invention is to control such combustion so as to permit higher compression ratios, without detonation, combustion roughness or the use of special fuels, with a resulting gain in power and economy.

A further object is to provide means for obtaining such combustion control.

Among further objects of the invention are:

To provide means for handling the fuel-air mixture or charge during compression so substantially homogeneous mixtures drawn from the carburetor and which are much leaner than a balanced mixture, can be fired positively and efliciently by a spark.

To provide means for handling the charge during combustion, so that importantly higher compression ratios can be used without detonation or combustion roughness.

Practical results of the leaner part load mixture and the higher compression ratio are to increase materially the power and economy of operation of the engine, to reduce carbon deposits in the combustion chamber and fuel dilution of the crankcase oil.

Another result is easier cold weather starting and an immediate full power drive away.

All these and other advantages will readily occur to those skilled in the art upon reference to the following description and the accompanying drawings in which:

Figure 1 is a sectional view as if on line 1-- 1 of Fig. 2 of the upper portion of one cylinder of a multicylinder L-head engine illustrating the invention;

Fig. 2 isa section .on line 2 2 of Fig. 1;

Fig. 3,is a view similar to Fig. 1 but showing a valvein-head engine, the section being taken on line 33 of Fig. 4;

Fig. 4 is .a View .of the underside of the head shown in Fig. 3;

Fig. 5 is a 'plan 'view of the underside of a portion of the cylinder head of an engine incorporating the invention in modified form;

Fig. 6 is a sectional view of the upper portion of the engine of Fig. 5 corresponding to a section on the line 66 of Fig. 5 andloofking in the direction of .thearrows;

Figs. 7 and 8 are respectively a top plan view .and a side elevation xof a detail of this embodiment Fig. 9 is a section on the line 9-9 of Fig. 5

Fig. 10. is a fragmentary sectional and partly diagrammatic view of a carburetor adapted for use with the 2,924,210 P t e F b.- 9, 960

2 engine shown in Figs. 5-9 and in the practice of my invention, and

Fig. 11 is a sectional elevational view of the metering jet and metering pin portions of a carburetor provided with a modified type of metering pin.

In the drawings there is shown only a single cylinder, and its head, of an internal combustiOn engine which may be a multicylinder engine of conventional construction throughout except for certain of the parts illustrated.

Referring to Figs. 1 and 2, a single cylinder of a conventional L-head block is shown at 10 with its piston 10A, combustion chamber 103, inlet and exhaust valves 10C and 10D respectively and water jacketing 10E.

The head of the cylinder is illustrated as being provided with a small chamber 11 communicating with the combustion chamber 10B through a passage 11A, a spark plug 12 being set in said small chamber.

It should be noted that the passage 11A opens into chamber 11 unsymmctrically and that the plug 12 is located at the chamber end close to the passage. It

, should also be noted that the geometric shape of chamber 11 should not be such as would be generated .by the rotation of a curve about its axis, but that the side wall should be of spiral form with a small gradual increase in radius. The passage 11A is tangential to the chamber and the spiral sb arranged that the larger radius portion is at one side of the passage with the spark gap at the end of the spiral.

It will also be seen from Fig. 1 that the floor of cha n.- ber 11 is elevated at short distance so that the bottom of passage 11A is above the level of the heads of valves 10C and 10D when the valves are closed.

In Figs. 3 and 4 a single cylinder of a multicylinder valve-in-head engine is shown at 110, piston at A, combustion chamber 110B, inlet and exhaust valves at 110C and 1101) respectively and water jacketing at 1105.

In these figures, the cylinder head is also shown as provided with a small chamber 111 communicating with the main combustion chamber 110B through a small passage 111A and into which is set a spark plug, the plug and the opening therefor being indicated at 112. Since, in the valve-in-head engine, the valves are above the combustion chamber 110B, the floor of chamber 111 including the passage 111A, may be the top surface of the block including cylinder 110.

In the operation of the engine, ,as the piston moves down with the inlet valve open, a charge .of fuel-air mixture is drawn in from the manifold and carburetor in the conventional manner. When the inlet valve closes and the piston moves up on the compression stroke, compressing the mixture, part of the latter will flow into chamber 11 through the passage 11A. Since the passage 11A opens unsymmetrically into chamber 11, the inflow causes a rapid rotation of the gases in the chamber and thereby, through centrifugal action, causes any liquid particles or fog of the fuel to ,be thrown toward the periphery of the rotating mass. And, as the mixture continues to be forced in through passage 11A, this band of richer mixture is driven ,np to the spark gap of spark plug 12.

Further, since the geometric shape of chamber 11 is not such as could be generated by the rotation of a curve about its axis, as the fluid in chamber 11 rotates under the drive of the blast coming in through passage 11A,.the chamber walls tend to knead the charge into an intimate mixture while quickly damping ,out the rotation when the exciting force subsides.

'By locating the spark close to the inner end of passage 11A, the ignited gases issue immediately into the combustion chamber 19 13, and since the axis of the passage is linedup with the most distant wall of the combustion chamber, the stream of ignited gases'is projected cent 3 trally through the compressed pinge forcibly on any metal surface;

The relative size of chamber 11 is so chosen that the fire blast issuing from passage 11A is-all absorbed bythe gases in" the combustion chamber B, the tongue of flame neither falling short of reaching across the combustion chamber nor A wall.

The cross-sectional area of passage'llAis so chosen with respect to the average of theflame front inchamber 11 that the velocity of the flame issuing from passage 11A into the combustion chamber 10B is approximately three times the velocity of a flame front in a. quiet mixture. Thus, by the time the flame front has advanced in chamber 11 only a short distance from the spark gap, the igniting blast issuing from passage 11A has crossed the combustion chamber 103 carrying ignition on both of its turbulent edges. i

In the conventional engine with spark ignition in the combustion chamber, combustion starts weakly from the spark and advances slowly on its initially"very limited flame front, but, as the flarne front increases in area and the temperature and pressurerise, the rate of combustion is expedited in the order of .the third power of elapsed time after sparking. This condition invites roughness and detonation.

On the other hand, in the present invention with the combustion being initiated in chamber 11, before normal propagation could reach the main combustion chamber, the pressure developed in chamber 11 will shoot an igniting flame entirely across the main combustion chamber on its longest dimension. Thus a flame front double the diameter of the combustion chamber is established immediately and flame proceeds in two directions with diminishing rates of pressure rise.

Referring now to the embodiment of Figs. 5-9 inclusive, a main combustion chamber is shownat 201, 'intake and exhaust valves at 205 and 206 respectively. Conventional rocker arms and pushrods entrained with tappets and .cams (not shown) actuate the valves 205 and 206. A piston 211 with compression rings -212 reciprocate in the cylinder .213. A piston pin 214 and a connecting rod 215 attach the said piston 211 to a crankshaft (not shown). The intake passage 216 terminating at its inner end in the valve seat 217 and the flow therethrough controlled by the valve 205, is connected at its outer end to a source of air-fuel mixture (not shown).

The exhaust port controlled by the exhaust valve 206 is in pipe connection at its outer end with an exhaust'manitold (not shown). All the structure referred to in this.

paragraph is conventional.

In addition to the conventional structure described,

the cylinder head is also provided with an initial eombustion chamber 202 at one side of the main combustion chamber and communicating therewith through the passages 209 and 210, the chamber and passages being preferably produced by suitable cores when the head is cast, the passages and chamber being open to the under face of the head member.

As shown in Fig. 5, both the side walls of the cham her 202, at the rear end of the chamber, are curved as at. 224, and meet centrally to provide a relatively sharp edge 220, and as shown in Fig. 6, these walls in their curved portion 224 are also curved in a .verticalplane so that the two streams of gases. coming in through the passages 209 and 210 are turnedinwardly toward each other. and also turned upwardly; t

Mounted in the upper wall of chamber. 202 isa sparkplug .203, in such position thatthe spark gap204 is in the upper and forwardportion. of the ehamberji Y The invention resides principallyin the relative size and shape of the initial combustion chamber. 202 and its relation to the main combustion chamber 201; the size and position of the passages 209 and .210 providing communication betweenthe initial combustion chamber yet heavily impinging on themetal mixture but willnot irn- H for cooling the separator 221, also means of forming the chamber 202 and the passages 209 and 210 and their closure at one side of the cylinder block 213.

In operation, during the compression stroke, the piston 211 forces mixture'into the chamber 202 through the t Fig. 9). Thus a richer fraction is abstracted from a lean a passages 209 and 210. The total cross-sectional area of the passages 209 and 210 as shown in the drawings, is less than half the cross-sectional area of the chamber 202 and is so chosen in proportion to the volume of chamber 202, that the velocity of inflow into chamber 202 during compression, is high. The inrushing mixture strikes the curving surface 224 and is turned 180. The centrifugal force tends to separate out any fuel particles or fog. The two streams of richer mixture moving on or near the surface .224, meetat the edge 220 .and are deflected by thetiltof the "surface 224 (see Fig. 6) toward the spark gap 204 and the pocket which is above and separated from the passages 209 and 210 (see mixture and carried to the area of the spark gap. 7 This gives a strong ignition which readily fires all the mixture in chamber 202. The projectionoftwo flames into the main combustion chamber 201, gives a positive and rapid ignition to the mixture therein .whether ultra lean or. balanced. p

The structure described in. the foregoingparagraph which enables the motor to fire perfectly on very lean mixture, also permitsa compression one or more ratios higher. As combustion 1 proceeds from-the spark gap 204, the areaof the flame front becomes larger than the combined cross-sectional areas of the passages 209 and 210. The velocity of discharge o f the burning gases is therefore higher than the orderly speed of -a flame front in a mixture. The passages 209 and 210 direct theflame toward the most distant wall ofthecombustion chamber,

and the volume of the ch amber 202 is so chosen that the issuing flames carry across but do on any wall of the chamber 201. Thus by the actual 5 transfer at high velocity ofiburning. gases, the rate of initial combustion is increased four to six times with a diminishing-rate of pressure rise as theflame burns through to'the. combustion chamber. walls'm places.

Thisrelatively rapid burnof th e;first two thirds of the charge with the ratesdiminishing to zero, is the opposite of conventional combustion-which starts slowly and builds up to a very rapid finish. Moreover, the

extreme turbulence inthe burning mixture, caused by impinging two high velocity flames into itggives a condition that suppressesdetonation. {The turbulence also gives such a thoroughmixture that escape, being compined with the oxygen of the charge early in the power stroke.

It is desirable that the volume of issuing from. passages 209 and 210respectivelyshouldbe proportional to the volume of compressed mixture into which it is thrown. In case the main combustion chamber 201 is not symmetricalwith the center line of the initialfcombustion chamber 202, the passage serving the largervolume as 210 (Figs; 5 and 9) is preferablylargerthan its companion passage209. It is desirable also that the center lines of passages. 209 and 210 be slightly divergent toward chamber 201 and that the cross-sectionalarea of.

each passage should increase progressivelyin the flow fromchamber202 to chamber 201. I j

Toiaidincooling the tongue of metal 221 between the. passages 209 and 210, a riv'etf222 ofcopperor other metal of high v thermal conductivity, and high melting point is inserted in a drilledholiein said tongue 221.. The rivet would 'betof aspectiallfor my-thehead flattened 1 to the same thickness as thelcylinder head gasket so it ill braigh a ainst-1 t e .i-sy r D 113- q 4,

not impinge forcibly few fuel molecules turned edge 227 (Fig. 8) would hold the head in angular position. The rivet preferably is tin plated toprevent oxidation and so improve heat flow through the surface and its head may, as .shown, be proportioned to underlie substantially all of the tongue portion 221. The rivet can be staked through the opening for the spark plug and the pocket 225.

As indicated hereinabove, my improved engine and method attain superior operation at less than full load with fuel-air mixtures leaner than normal. In fact, at light loads, perfect firing is attained with 100% excess air over that required for combustion. Of course in order to develop full power, a full balanced mixture should be supplied at full loads. The invention is also productive of important benefits when so operating at full loads with a normal mixture. Due to the projection of the flaming jet or jets into the main charge from the precombustion chamber, the initial rate of flame propagation is much higher than in conventional engines, although the rate of combustion slows toward the end. This is opposite to conventional practice, in which the initial rate of flame propagation is slow, but increases rapidly toward the end. The latter characteristic of conventional engines is regarded as 'a cause of detonation. My invention operates with less detonation and with a much later spark setting at full loads. This elimination of the need for a greatly advanced spark at high engine loadings also eliminates the negative work and heat loss occasioned in conventional engines by the early spark and partial burning of the charge long before the piston reaches dead center.

As previously indicated, the carburetor and fuel supply means may be conventional in construction. .In Fig. 10 I have indicated, somewhat diagrammatically, essential portions of a conventional carburetor adapted to supply the engine of Figs. 5-9. Gasoline is supplied from a carburetor float bowl 230 through metering jet orifice 232, passages 233 and nozzle 234 into the throat of the carburetor, where the gasoline is atomized and mixed with the .inflowing air, and carried past the throttle valve 235 and through the manifold passages and inlet passages as 216 (Fig. 6) to the cylinders.

As shown in Fig. 10 .the metering valve pin, generally designated 236, has an upper cylindrical portion 238 which is somewhat smaller in diameter than the metering jet orifice 232, and a lower endportion 240, which is also cylindrical, and which is of smaller diameter than the upper portion 238 and joined thereto by a relatively abrupt shoulder 242. The metering pin is so connected to the operating means for the throttle valve 235 that movement of the throttle operating link 250 to a position to fully open the throttle, moves the metering pin upwardly so that only the small portion 240 obstructs the metering jet orifice, and the effective cross section of the orifice is then great enough to supply a full balanced mixture. As the throttle is moved toward closed position, the metering pin moves downwardly, and for .approximately the first ten degrees of movement of the throttle valve toward the closed position, only the small pin portion 240 is in the orifice 232, so that the full mixture is supplied until, as the shoulder 242 reaches the small portion of the orifice, the efiective cross section of the orifice is reduced by the entry of the larger diameter portion 238 thereinto. The portion 238 is of a diameter such as to admit fuel in proportion to the air in a quantity only suflicient to provide approximately one half a balanced mixture, and as the cylindrical portion 238 continues "to move downwardly, in response .to further closing movement of the throttle, the reduced mixture is maintained right down to idle.

Fig. 11 illustrates amodification wherein the metering pin is provided with a cylindrical lower portion 240A, proportioned and positioned to provide .a full balanced mixture at full throttle, and corresponding to the part 240 of Fig. 10. The length of part 240A may be such as to maintain a full balanced mixture as the pin moves downwardly during an initial increment of closing movement of the throttle from full open (e.g. 10). Above the cylindrical lower part 240A the pin is provided With a portion 242A of gradually increasing diameter and which tapers outwardly and upwardly and which at its upper end is joined to a cylindrical portion 238A which is of a diameter to maintain a desired lean mixture. This cylindrical part 238A is in the light throttle range, and its diameter may be such as to .supply approximately one half of a balanced mixture. When the pin is moved downwardly all the way, however, to the position it occupies at idle, a somewhat reduced portion 252 of .the pin is brought into the metering orifice, thereby somewhat enlarging the efiective orifice at idle. This reduction of diameter need only be .sufiicient to insure smooth idling, and may either be a full balanced mixture, or somewhat less than a full balanced mixture, as the nreferance of the desi ner and the operating characteristics of the engine may dictate. It will also be realized that the contour of the metering pin may be varied in other ways to give the best performance, and that this may be experimentally determined for each type of engine to which my invention may be applied. With the provision of an inclined portion, such as the portion 242A, as the throttle is moved toward the closed position in this range, the metering pin gradually reduces the efiective cross section of the jet orifice 232 more rapidly than, and to a leaner mixture than, do the designs employed in conventional engines. It will be appreciated also that in varying the contour of the pin, such a graduated portion, instead of having a straight taper as does the portion 242A, may be longitudinally curvedlto vary the rate of change of the effective orifice diameter during throttle movements.

With conventional engines, the metering pin or other gasoline flow-controlling means of the carburetor is designed .to tend to maintain substantially a balanced mixture at all throttle settings. In contrast, -I modify this means in such manner as to reduce the mixture to .a lower fuel-air ratio as the throttle is moved toward closed position, and vice versa. .Although with a carburetor of the indicated variety this is done by modifying the metering pin, it will be appreciated that other types of gasoline flow-regulating means may readily be modified in an analogous manner. Tests have indicated that the proportioning of the valving end of the metering pin of a carburetor of the type illustrated may be such that at approximately half loads, the amount of fuel supplied may be approximately one half normal, as indicated. Thus the metering pin (or the other gasoline flow-controlling means of the carburetor) is so designed as to vary the mixture between a full mixture at ,full load and a relatively very lean mixture at part load.

In the" particular carburetor illustrated, the throttle actuating arm 250 is presumed to be actuatable in conventional fashion by an accelerator pedal, and is connected to arm 254 of an angularly adjustable crank assembly comprised of arms 254, 255, rockable as a'unit about the axis of their supporting shaft 256. Arm 255 is connected by a link 245 to a lever 246 rockable upon a fulcrum shaft 248, the upper end of the metering pin 236 being articulated to the arm .246 between'the fulcrum 248 and the point of connection of :link 245, as shown in Fig. 10. Arm 254 is also connected by link 260 to throttle valve actuating arm 262, which is fast with respect to throttle valve 235, so that the throttle is moved toward closed position as the metering pin 236 is moved downwardly, and vice versa, in the manner above de scribed.

It will be appreciated that many carburetors of this general class are provided with manifold pressure-responsive or so-called vacuumemeter :means, .so arranged as to tend to :move themetering pin :to, or hold it .in, an open position if the manifold pressure rises too high (vac- "'7 uum falls away) thus tending, to maintain or establish a richer mixture when engine loading makes it desirable at part throttle. Such aprovision is of course desirable but is not'a part of my invention and would have no bearing upon the operation of my improved engine except, as with conventional engines, to tend to maintain a richer mixture when the engine is heavily loaded at part throttle The construction of the carburetor, as well as the means for regulating or metering the flow of gasoline is. subject to wide variation in other respects,, and in fact different constructions are employed for this purpose by different carburetor manufacurers; The means employed to perform this function does not in itself constitute an essential element of the present invention, except to the extent that it provides means for varying the mixture so that when the throttle is operated in the normal. manner, and the engine is operating under normal conditions, the supply of liquid gasoline will .vary between a lean mixture at light loadsand a normal balanced mixture at full load. The specific illustrated forms of the other conventional engine components are of course also shown by way of example.

What is claimed is: V

1. In an internal combustion engine having a portion defining an enclosed space constituting a cylinder portion and a main combustion chamber portion, means for introducing into said space a charge of generally homogeneous pre-carbureted air constituting the full airfuel charge for said cylinder, a piston reciprocable in said cylinder portion toward and from the said main combustion chamber portion, means defining an initial combustion chamber having no separate fuel charging means, said initial combustion chamber being separated from said space, and a restricted opening portion providing communication between said initial combustion chamber and said main combustion chamber portion, said initial combustion chamber having a concavely curved Wall portion substantially tangent to the path of gases entering said initial combustion chamber from the main combustion chamber portion through said opening portion, localized ignition means in said initial combustion,

chamber positioned in the path of gases which may be guided by and along said curved wall portion, the restriction and direction of said opening portion being such as to direct an accelerated infiowing'streamof the airfuel charge into the initial combustion chamber and substantially tangentially against and along said curved wall portion in response to movement of the piston toward the main combustion chamber portion, and to direct an accelerated flaming jet into said main combustion chamber portion from said initial combustion chamber when firing is efiected in said initial combustion chamber by said ignition means, the curved wall portion being interposed in the path of said inflowing stream between the opening portion and the ignition means to impart angular movement to said infiowing stream, thereby tending to separate heavier fuel components in said inflowing stream centrifugally. and to guide and direct them toward said ignition means.

2. In an internal combustion engine as defined in claim 1, cooling means for extracting heat from said curved wall portion.

3. In an internal combustion engine having a portion defining an enclosed space constituting a cylinder and a main combustion chamber, means for introducing into said space a generally homogeneous charge of pre-carbureted air. constituting the full air-fuel charge for said cylinder, a piston reciprocable in said space toward and from said main combustion chamber portion thereof, means defining an initial combustion chamber having no separate fuel charging means, means defining a pairof restricted passages interconnecting laterally spaced portions of said initial combustion chamber with said main combustion chamber portion; a partitioning wall located between said passages and separating said initial combustion chamber from said space, said initialcombustion cham ber havingtwo concavely curvedwall portions, each of which is substantially tangent to an outer wall of one of said passages, said curvedwall portionscurving toward one another and defining'th'e outer walls of said initial combustion chamber and curving re-entrantly inwardly with respect to said initial combustion chamber and forming at their juncture a generally. pointed centrally dis posed wall portion directed toward said partitioning wall, a'spa'rk plug having electrodes located in said initial combustion chamber'substantially on a line between said pointed wall portion;and said partitioning wall, the restriction and direction of each of said passages being such as todirect an accelerated inflowing stream of the airfuel charge into theinitial combustion chamber during movement of the piston toward the main combustion chamber and to direct an accelerated flaming jet into said proximity to said curved walls, said curvedgwalls and saidpointed juncture thereof being positioned to direct said heavier componentstoward said electrodes.

4. An engine construction as definedin claim 3having a separable water jacketed head, said main combustion chamber portion and said initial combustion chamber being formed in said head, a water jacketed portion in said head appurtenant to said curved wall portions for extracting heat from the latter, a water jacketed block portion defining the cylinder portion of said space, and

a heatconductive metallic portion incorporated in said partitioning wall and bearing against said block.

5. An engine as defined in claim 1 wherein said ignition means is located closer to said opening than is at least a portion of said initial combustion chamber, whereby upon firing of the ignition means a portion of the flame front moves outwardly through the opening and into said space and a portion of the flame front moves into portions of the initial combustion chamber spaced fromthefopening to increase the pressure in the initial combustion chamber. t

6. An engine as defined in claim 3 wherein said ignition means is located closer to said passages than is at least a portion of said initialcombustion chamber, whereby upon firing of the ignition means a portion of the flame front moves outwardlythrough the passages and into said space and a portion of the flame front moves into portions of the initial combustion chamber spaced from the passages to increase the pressure inthe initial combustion chamber.

7. An engine as defined in claim 1 wherein said opening opens into said main combustion chamber ina direction substantially transverse to the direction of movement of the piston and is, soproportioned that ablast of flame is directed into the main combustion chamber through said opening upon ignition of the charge within said initial combustionchamber with a force sutficient to carrysaid blast substantially entirely across the main tially entirely across the main combustion chamber With-T out impinging heavily against the opposite side of said main combustion chamber.

9. In an internal combustion engine, a main combustion chamber and an initial combustion chamber, a pair of passages converging toward the latter and affording communication between the :two chambers, the combined cross-sectional area of the passages being less than half the cross-sectional area of said initial combustion chamber on any medial plane, said initial combustion chamher having a vertically arranged V-shaped inwardly projecting rear wall, the side walls of said initial combustion chamber being continuations of the outer side walls of said passages and being curved and having the curvature continued to meet at the apex of the V-shaped rear Wall, said rear wall being also vertically inclined, and a spark plug fixed in the upper wall of said initial combustion chamber with its spark gap central laterally of the latter and substantiallyover the inner ends of the passages.

10. An internal combustion engine as defined in claim 1 including a block containing said cylinderdefining portion, and a removable head with a substantially planar bottom face adapted to fit over and substantially close the cylinder-defining portion, both the main combustion chamber portion and the initial combustion chamber being formed in said head and opening in said bottom face thereof, said block having a substantially planar head-supporting wall extending outwardly from the end of said cylinder-defining portion nearest to said main combustion chamber portion, the open portion of said initial combustion chamber overlying and being closed by said head-supporting wall, said restricted opening comprising a groove in said bottom face of the head.

11. Means as defined in claim including a second groove forming a second such restricted opening between the initial combustion chamber and the main combustion chamber portion, said grooves opening into the main combustion chamber portion at spaced positions and also opening into said initial combustion chamber at spaced positions, each of said grooves communicating with an individual curved wall portion within the initial combustion chamber, the two curved wall portions intersecting one another at a position substantially midway .between said grooves and defining a linear projection at the position of intersection, such linear projection lying in a plane substantially perpendicular to said planar bottom face of the head and projecting in a direction generally toward said ignition means.

12. Means as defined in claim 10 including a second groove forming a second such restricted opening between the initial combustion chamber and the main combustion chamber portion, said grooves opening into the main combustion chamber portion at spaced positions and also opening into said initial combustion chamber at spaced positions, each of said grooves communicating with an individual curved wall portion within the initial combustion chamber, the two curved wall portions intersecting one another at a position substantially midway between said grooves and defining a linear projection at the position of intersection, such linear projection lying in a plane substantially perpendicular to said planar bottom face of the head and projecting in a direction generally toward said ignition means, the ignition means comprising a spark plug having electrodes opening into said initial combustion chamber at a position spacedly above said open lower portion of the initial combustion chamber, and said projection being inclined upwardly in a direction to project inflowing gases upwardly toward said electrodes.

-13. An internal combustion engine as defined in claim 1 wherein the are of curvature of said concavely curved wall portion is non-circular.

14. An internal combustion engine as defined in claim 1 wherein the arc of curvature of said concavely curved wall portion is non-circular, and is of decreasing radius in a direction away from said opening and toward said ignition means.

15. An internal combustion engine as defined in claim 3 including a block portion containing said cylinder and a head portion containing both the main combustion chamber and the initial combustion chamber, both of said combustion chambers opening into a generally planar face of said head which is adapted to overlie said block, with the main combustion chamber at least partially overlying an end of said cylinder and the initial combustion chamber overlying a wall of and being substantially closed :by said block, said passages being formed by open-sided channels in said face of the head.

16. An .internal combustion engine as defined in claim 3 including a block portion containing said cylinder and a head portion containing both the main combustion chamber and the initial combustion chamber, both of said combustion chambers opening into a generally planar face of said head which is adapted to overlie said block, with the main combustion chamber at'least partially overlying an end of said cylinder and the initial combustion chamber overlying a wall of and being substantially closed by said block, said passages being formed by open-sided channels in said face of the head, and cooling means communicating with a wall of said initial combustion chamber for extracting heat therefrom.

17. In an internal combustion engine as defined in claim 15,, .-a water jac'ketin'g portion formed in said block and having a top -wall portion which is overlain by said initial combustion chamber and by said partitioning wall, and metallic heat conducting portions in intimate heat conductive association with said partitioning wall and adapted to bear directly upon said top wall portion of said block to conduct heat from said partitioning wall in the head to said water jacket in the block.

18. In an internal combustion engine as defined in claim 17, gasket means interposed between the block and head, said heat conducting portions extending through an opening in said gas'keting and including a portion bearing directly against the block to provide a heat path from the partitioning wall to the block without requiring the conduction of heat through said gasket.

19. In an internal combustion engine as defined in claim 17, gasket means interposed between the block and head, said heat conducting portions extending through an opening in said gasketing and including a portion hearing directly against the block to provide a heat path from the partitioning wall to the block without requiring the conduction of heat through said gasket, said initial combustion chamber having a top wall spaced from said planar face of the head, said spark plug being mounted in said top wall, said electrodes being spaced above said face, the pointed juncture of said concavely curved wall portions defining a generally knife-edged portion inclined upwardly and outwardly with respect to said initial combustion chamber, whereby "fuel is directed upwardly as well as inwardly from said knife-edged portion.

20. In an internal combustion engine as defined in claim 18, an opening-defining portion in said gasket aligned with said open bottom of said initial combustion chamber whereby said top wall of the water jacketed portion of the block is directly exposed to the interior of said initial combustion chamber .for direct absorption of heat therefrom.

21. In an internal combustion engine as defined in face and through said cut away portion a distance con-' forming substantially to the efiective thickness of the gasket and bearing against said block, whereby heat in said initial combustion chamber and in said partitioning wall may be directly conducted 'into the block without passing-through the gasket, and heat disposal means associated with said block.

22. An internal combustion engine as defined in claim 1 having poppet-type inlet and outlet valves opening into said main combustion chamber and movable inwardly of said main combustion chamber during opening movement thereof, said restricted opening portion being positioned to direct flaming gases flowing outwardly from said initial combustion chamber through said opening in a direction to prevent substantial impingement thereof against eitherof said valves.

23. An internal combustion engine as defined in claim 1 wherein said initial combustion chamber and said restricted opening are so proportioned with respect to the main combustion chamber that the fire blast issuing from the initial combustion chamber through'said opening as a result of ignition within said initial combustion chamber is substantially all absorbed by gases in the main combustion chamber without permitting heavy impingement of the fire blast against the wall of the main combustion chamber. i

24. An internal combustion engine as defined in claim 3 wherein said main combustion chamber is not symmetrical, s o thatzones of differing volume lie upon opposite sides of a centerline projected throughthe initial combustion chamber and into the main combustion chamber midway between said passages, and wherein said passages are of dilferent effective cross-sectional area, the passage of greater area lying on the side of said centerline toward the zone of said main combustion chamber which is of greater volume.

25. In a piston-type internal combustion engine having a main combustion chamber within which explosions occur to actuate the piston, means for delivering directly into the main combustion chamber a charge of pre-carbureted air containing a fuel which is heavier than air, and means for firing the charge in said main combustion chamber comprising a portion defining a pre-combustion chamber, a restricted port providing communication between said pre-combustion chamber and said main cmbustion chamber, and an igniting device in said pre combution chamber, a charge rotating portion within said pre-combustion chamber for imparting angular velocity to a portion of the charge forced into said pre-combustion'chamber by said piston, said igniting device being located in the path of heavier components of the charge separatedby said charge rotating portion, said restricted port being so proportioned with respect to both the pre-combustion chamber and the main combustion chamberas to direct into the main combustion chamber from the pre-combustion chamber, upon ignition of the charge in the pre-combustion chamber, a fire blast which is projected substantiallyentirely across the main combustion combustion chamber but of insuflicient velocity to impinge heavily against the opposite side of said main com-- bustion chamber. i

26. In an internal combustion engine of the type having a cylinder and a piston actuable therein and a main combustion chamber. appurtenant to the cylinder and within which explosions occur to actuate the piston, means for delivering .directly to said main combustion chamber a substantially homogeneous charge of pre-,

carbureted air containing a fuel having flammable components heavier than air and constituting the entire charge for the cylinder, a pre-combustion chamber, ig-

niting means within said pre-combustion chamber, re-.

the main combustion chamber, thereby tendingto sepa-,

rate and concentrate such heavier flammable components t 12 Y in a predetermined region within said pre-combustion chamber, said ignitingmeans being located in 'said region, whereby such heavier concentrated components may be ignited by said igniting means, and whereby upon such ignition a tongue of flame is ejected into the main combustion chamber from said pre -combustion chamber through said port-defining portions. I

27. The method ofoperating an internallcombustion engine of the piston type having a main combustion chamber within which explosions occur to actuate the piston and having a centrifugal charge-rotating type precombustion chamber restrictedly intercommunicating with said main combustion chamber and anigniting device within said pre-combustion chambenwhich comprises introducing directly into said main combustion chamber during each charging stroke a full charge of substantially homogeneous pre-carbureted mixture which is of leaner than balanced proportions, forcing a portion of said full charge into the, pre-combustion chamber by movement of the piston only, and impartingrotary movement to said portion of the charge within the pre-combustion chamber to concentrate heavier proportions of such portion of the charge-in the area of the igniting device, igniting such vheavier proportion of the charge within said pre-combustion chamber, and directing a flaming blast resulting from such ignition into the main combustion chamber through said restricted intercommunication.

-28. The, method of operating an internal combustion engine of the piston type having a main combustion chamber, within which explosions occur to actuate the piston and having a centrifugal charge-rotating type precombustion chamber restrictedly intercommunicating with said main combustion chamber, and an, igniting device within said precombustion chamber, which comprises introducing directly into said main combustion chamber during each charging stroke a full charge of within said precombustion chamber, and directing flame resulting from such ignition into the main combustion chamber by way of said restricted intercommunicationr 29. In an internal combustion engine of the type having, a cylinder and apiston actuable therein and a main combustion chamber appurtenant to the cylinder and within which explosions occur to actuate the piston, passage, means for delivering directly to said main combustion chamber asubstantially homogeneous charge of pre-carbureted air containing a fuel which is heavier than air and constituting the entire charge for the cylinder, a carburetor having an air inlet portion, a fuel supplying portion a carbureting portion for charging the air with fuel, an outlet for the carbureted air mixture, said outlet communicating with said passage means, a

throttle valve for regulating the flow of the air-fuel mix-r ture, a fuel valve movable between a restricting position and a full flow position to vary the fiow of fuel from said fuel supplying portion to the carbureting portion,

said fuel valve having 'a restricting portion which, when said fuel valve is inthe, restricting position, permits a flow of fuel substantially lessthan that required to fully charge the air to balanced proportions, means intercom-y necting the fuel valve and the throttle valve to move;the

fuel valve to said restricting position as the throttle valve, is moved toward a closed position, and to movethe fuel valve to the full flow position which permits a flow, of fuel'sufficient to supply a balanced mixture when the, throttle valve i opened, a pre-combustion @hflfilbcr) igniting means within said pre-combustion chamber, restricted port-defining portions interconnecting said precombustion chamber and said main combustion chamber and constituting the only operative interconnection between said chambers, a charge rotating portion in said pre-combustion chamber adapted to impart angular mo mentum to a portion of the charge forced into said precombustion chamber by movement of the piston toward the main combustion chamber, thereby tending to separate and concentrate such heavier flammable components in a predetermined region within said pre-combustion chamber, said igniting means being located in said region, whereby such heavier concentrated components may be ignited by said igniting means, and whereby upon such ignition a tongue of flame is ejected into the main combustion chamber from said pre-combustion chamber through said port-defining portions.

30. An engine as defined in claim 29 wherein the throttle valve is continuously variable between said open position and an idle position, and said interconnecting means moves the fuel valve to an increased flow position as the throttle valve is moved to the idle position.

31. An engine as defined in claim 29 wherein the throttle valve is continuously variable between said open position and an idle position, and said interconnecting means moves the fuel valve to an increased flow posi- 14 tion as the throttle valve is moved to the idle position, and causes continuous variation of the position of the fuel valve during movement of the throttle valve through a range of intermediate positions.

32. The method defined in claim 28 wherein the airfuel proportioning is continuously varied between said substantially balanced mixture at full throttle and said leaner mixture at part throttle including the further step of increasing the fuel-to-air ratio above that of said leaner mixture as the throttle setting is reduced below such part load setting and to an idle setting.

33. A method as defined in claim 28 wherein the airfuel proportioning is varied continuously during at least a portion of such varying of the throttling of the charge.

34. An engine as defined in claim 29 wherein said restricting portion of the fuel valve is graduated to provide a continuously varying amount of restrictive eflect during movement of the fuel valve through a range corresponding to movement of the throttle valve throughout a part throttle range.

Bicknell Nov. 5, 1946 Jones Feb. 26, 1957 

